Utilization and cost of drugs for diabetes and its comorbidities and complications in Kuwait

Abstract

Background Diabetes imposes a large burden on countries’ healthcare expenditures. In Kuwait, diabetes prevalence in adults is estimated at 22.0%%—double the worldwide prevalence (9.3%). There is little current data on pharmaceutical costs in Kuwait of managing diabetes and diabetes-related complications and comorbidities. Objectives Estimate the utilization and cost of drugs for diabetes and diabetes-related complications and comorbidities in Kuwait for year 2018, as well determinants of costs. Methods This cross-sectional study used a multi-stage stratified sampling method. Patients were Kuwaiti citizens with diabetes, aged 18–80, recruited from all six governorates. Physicians collected demographic data, clinical data, and current drug prescription for each patient which was extrapolated for the full year of 2018. A prevalence-based approach and bottom-up costing were used. Data were described according to facility type (primary care vs. hospital). A generalized linear model with log function and normal distribution compared drug costs for patients with and without comorbidities/complications after adjustments for demographic and health confounders (gender, age group, disease duration, and obesity). Results Of 1182 diabetes patients, 64.0% had dyslipidemia and 57.7% had hypertension. Additionally, 40.7% had diabetes-related complications, most commonly neuropathy (19.7%). Of all diabetes patients, 85.9% used oral antidiabetics (alone or in combinations), 49.5% used insulin alone or in combinations, and 29.3% used both oral antidiabetics and insulin. The most frequently used oral drug was metformin (75.7%), followed by DPP4 inhibitors (40.2%) and SGLT2 inhibitors (23.8%). The most frequently used injectables were insulin glargine (36.6%), followed by GLP-1 receptor agonists (15.4%). Total annual drug cost for Kuwait’s diabetic population for year 2018 was US$201 million (US$1,236.30 per patient for antidiabetics plus drugs for comorbidities/complications). Conclusions Drug costs for treating diabetes and comorbidities/complications accounted for an estimated 22.8% of Kuwait’s 2018 drug expenditures. Comorbidities and complications add 44.7% to the average drug cost per diabetes patient.